Over the recent years, with higher-functionalization of information processing devices such as mobile phones and personal computers, the majority of information processing devices each include a plurality of units which transfer data (which will hereinafter be referred to as data transfer units) such as a communication unit for performing wireless communications and a wired communication unit using a LAN cable.
For example, there is known a technology by which two communication units, i.e., a first communication unit and a second communication unit transfer and receive data (Japanese Patent Application Laid-Open Publication No. 2005-020477). Further, e.g., there is known a technology for preventing redundancy of an authenticating operation between two systems by transmitting and receiving authentication information between an authentication center held by a mobile network operator and an authentication server of a wireless LAN system (Japanese Patent Application Laid-Open Publication No. 2003-348655).
The prior arts, however, actively utilize the plurality of data transfer units in the information processing device. Therefore, for example, one of the plurality of data transfer units is connected to a closed network such as an intra-office network, in which case such a problem could arise that information existing on the closed network is leaked to an external network due to connecting other data transfer units in the plurality of data transfer units to the external network.